Rotor arrangements of the above mentioned general type that are free of flapping hinges are known in the art, for example as disclosed in U.S. Pat. No. 5,263,821. Such rotor arrangements generally include a centrally located, very stiff and rigid plate component of fiber-reinforced composite material that is rigidly connected to the rotor mast. The plate component is provided with blade connection arms that are integrally formed on the plate component and extend radially outwardly therefrom. The blade connection arms form the effective or fictitious flapping hinges and therefore must be embodied with sufficient flexibility or bending elasticity. However, in order that the blade connection arms surely and reliably withstand the high bending moments as well as the transverse and centrifugal force loads that arise during operation of the rotor, the blade connection arms must have a large bending length. As a result, disadvantageously, the fictitious flapping hinges are located relatively far from the center point or axis of the rotor, namely at a spacing of approximately 10% of the rotor radius away from the rotor center, and therefore, very interfering and dangerous vibrations arise in the rotor arrangement and in the helicopter during flight.
It is also known in the art, for example from the International Patent Publication WO 87/04402 and U.S. Pat. No. 4,568,244, to embody the blade connection arms separately from the stiff and rigid rotor head plate, and instead to supportingly connect the blade connection arms to the rotor head plate in a manner allowing flapping angle movement, using elastomeric bearings arranged relatively close to the rotor axis, for example. Such an arrangement allows the spacing of the flapping hinges away from the rotor center to be reduced to a desired dimension, namely for example approximately 5% of the rotor radius, and thereby allows interfering vibrations caused within the rotor to be substantially suppressed. On the other hand, such a rotor arrangement is structurally very complicated and costly, and very sensitive to wear, so that it can only meet the requirements of robust reliability and low maintenance in very limited circumstances.